Neil, This has to do with the caloric demand of phase transiion, i.e., one calorie = the energy required to heat 1 cc of water 1 deg. C... until it reaches 100 deg C... then to heat it one more degree (make it boil... in other words, go from liquid to gas) it requires 100X (or is it 10x?, those pesky decimal points always bugger me up!) the required energy. Solder changing from solid to liquid is a phase transition as well, so similar physics apply. Here's a neat idea how to tell for sure: Get your hands on an electric meter, the kind they have sealed to your house, and put it in line with the solder machine. Try scenario "A" for a month and record the power consumption, likewise "B" then compare... The proof is in the pudding, don't you think? I'd be very interested to hear your findings! Good luck, Ed Popielarski QTA Machine 10 Mc Laren, Suite D Irvine, Ca. USA 92618 Ph: (949)581-6601 Fx: (949)581-2448 E-Mail: [log in to unmask] http://www.qta.net ASK ABOUT OUR BGA REBALLER! ################################################################ TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c ################################################################ To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TechNet <your full name> To unsubscribe: SIGNOFF TechNet ################################################################ Please visit IPC's web site (http://www.ipc.org) "On-Line Services" section for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################ ################################################################ TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c ################################################################ To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TechNet <your full name> To unsubscribe: SIGNOFF TechNet ################################################################ Please visit IPC's web site (http://www.ipc.org) "On-Line Services" section for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################